There have been many attempts to sheet a bed or stretcher from a roll of sheeting material secured to the bed or stretcher. Many of these proposed the use of a dispensing roll at one end of the stretcher and a take-up roll at an opposite end of the stretcher. Such a system is not desirable because it stores the contaminated sheet on the take-up roll where is could possibly cross-contaminate patients using the same stretcher even though a new section of sheeting were advanced between the two rolls.
It has also been proposed to use a single dispensing roll and sever the sheeting and to discard it immediately after use. Various severing mechanisms have been proposed, such as knife-like structures at the end of the stretcher. Such knife cutters require continual maintenance to insure their sharpness and they can frequently malfunction. There is also the problem of having to measure each length before cutting it. Some examples of patents on roller dispensing sheet systems for stretchers or beds are U.S. Pat. Nos. 2,339,828; 2,466,679; and 3,641,600. One patent, U.S. Pat. No. 3,956,782, describes a sheet with sealed corners forming a "fitted " sheet of a precise length and width and a series of such sheet joined together by a series of perforations. The perforations were spaced apart a distance essentially equivalent to the mattress length. Such a fitted sheet was not suitable to take on varying lengths and widths of mattresses, such as might occur in stretchers of different manufacturers, models, styles, etc. The mattresses could also vary in thickness from approximately 2 inches to 8 inches.